PROJECT SUMMARY/ABSTRACT In the United States, African Americans (AAs) have a stroke risk twice that of Caucasians. The third-leading cause of death for women, stroke affects women more than men. Physiological changes due to pregnancy increase risk of stroke during the third trimester of pregnancy and postpartum. There is some evidence, primarily from Northern European populations, that the elevated risk may persist for years after delivery. The American Heart Association (AHA) recognizes pregnancy complications as risk factors for stroke in women, but called for more research among AA women on this topic?especially as AA women have a higher burden of pregnancy complications and there have been almost no studies on pregnancy complications and stroke in AA women. We propose to address this information gap in a population with a high prevalence of pregnancy complications, high burden of multiple life adversities, and a high risk of stroke, in the first large longitudinal study of AA women for this purpose. The Black Women's Health Study, begun in 1995, follows 59,000 AA women from across the U.S. and collects data every 2 years. Respondents have reported 1,845 incident strokes and 96,466 pregnancies since the study commenced. We propose to develop a resource for research on stroke in AA women by validating the self-reported stroke cases in the BWHS through medical records and Medicare linkage. We propose to assess whether pregnancy complications (preterm delivery, preeclampsia, gestational diabetes), individually and jointly, are associated with a higher risk of incident stroke in AA women in later years. We will also evaluate possible modification of the associations by factors such as healthy lifestyle (e.g., maintaining healthy post-pregnancy body mass index, healthy diet, non-smoking, physical activity) or by experiences of adversity (physical/sexual abuse, low socioeconomic status, experiences of racism and discrimination). We will investigate hypertension, type 2 diabetes, and depression as potential mediators that underlie the progression from pregnancy complications to stroke. The proposed study will be the first to address a critical unknown?whether and how pregnancy complications contribute to stroke incidence in AA women, a vulnerable population at high risk for pregnancy complications and stroke. The study will advance our understanding of potential mitigating factors postpartum that could lower risk of stroke for AA women. Knowledge gained from this proposal could inform patients, clinicians, researchers, and policy makers, and increase awareness' of pregnancy complications as stroke risk factors for AA women.